Expression of the Vascular Endothelial Growth Factor C (VEGFC), an activating ligand to the VEGF Receptor 3 (VEGFR3) specific to the tumor-associated lymphatic endothelium, is associated with increased lymphatic vessel density, lymphovascular invasion, and overall poorer prognosis in both murine models of breast cancer and patients [1, 9, 11, 12]. This evidence concerns the gene FLT4 and breast cancer.